The imposing portrait of Mao Zedong that looms over Tiananmen Square is one of China's most instantly recognizable images. However, not many people know the stories behind that iconic painting.

Ever since the portrait was first unveiled in Tiananmen Square at the founding ceremony of the People's Republic of China (PRC) on October 1, 1949, it has been replaced by a new copy almost every year on National Day. But the size of the portrait has basically remained unchanged since then. Measuring 6 meters high and 4.6 meters across, it is often assumed to be the largest portrait of Mao in China.

In fact, from the 1960s to the 1970s, People's Square in Shanghai had its own rotating portrait of Chairman Mao. They were much larger than the ones in Tiananmen Square, measuring 9 meters high and 6.9 meters wide.

From 1963 to 1978, on the eve of nearly every National Day, Shanghai-based painter Shen Chongdao would stand on a temporary scaffolding platform in People's Square for at least 10 days. His gray work clothes were always stained with paint. In front of him was a huge canvas on which a portrait of Chairman Mao would gradually appear. Shen was just one of the painters of the Mao portraits that hung in People's Square.

Although Shen never personally met the Great Helmsman, he saw Mao's face every day from 1963, when he graduated from Zhejiang Academy of Fine Arts (today's China Academy of Art), until 1978. Employed by the Lead Portrait Group of the Shanghai Arts and Design Company (SADC), Shen's job was to depict China's leader.

From the 1950s to the 1970s, SADC was one of only two organizations in China authorized to produce so-called "standard" images of the Chairman.

Every portrait of Mao had to strictly follow the likeness from a black and white photo of Chairman Mao shot in 1964, which was called No.4 Standard Picture of Mao Zedong. The portrait that hangs in Tiananmen Square today was also replicated from this No.4 photo.

"Our painters in that group perhaps couldn't be regarded as real artists at the time since we were not allowed to sign our names on any of the portraits we produced," Shen told the Global Times. "And all of our finished works were strictly examined by our leader, and later, they were sold in batches by factories, mines, schools and other government authorities."

To this day, Shen, now 74 years old, still considers what he did very honorable work. He emphasized to the Global Times that only the most outstanding graduates from professional art institutions were asked to paint Mao's image.

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